It is most probably that you didn’t use the username we sent you to log in.
It is most probably that you didn’t use the username we sent you to log in.
If you compare upper-case I and lower-case L side by side, L is taller and I is shorter.
It is most probably that you didn’t input the account name or password correctly.
No, you CAN NOT. You should always use the username (also known as account name or login name) we sent you to log in the game and the RS official website.